Power transistors commonly employed in automotive and industrial electronics should have a low on-state resistance (Ron·A), while securing a high voltage blocking capability. For example, a metal oxide semiconductor (MOS) power transistor should be capable, depending upon application requirements, to block to drain to source voltages Vds of some tens to some hundreds or thousands volts. MOS power transistors typically conduct very large currents which may be up to some hundreds of amperes at typical gate-source voltages of about 2 to 20 V.
A concept for transistors having a further improved Ron·A characteristic refers to lateral power trench metal oxide semiconductor field effect transistor (MOSFET). Lateral power trench MOSFETs utilize more bulk silicon for reducing Ron so that Ron is comparable to that of a vertical trench MOSFET.
Monitoring the temperature inside the transistor cell array of a power transistor has become increasingly important. For example, it may be determined whether the temperature inside the power transistor exceeds a certain threshold value so that the transistor may be switched off when the threshold temperature is exceeded. Further, it may be desirable to measure the temperature inside the transistor cell array. Therefore, it may be desirable to integrate a temperature sensor into a power transistor.